Introdução: A diarréia por Clostridium difficile é uma das principais causas de diarréia infecciosa associada à assistência à saúde. Objetivo: Descrever os casos e a incidência de diarréia por C. difficile em pacientes hematológicos e TCTH internados na enfermaria da Hematologia e do Transplante de Medula óssea do Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Métodos: Foi utilizada uma ficha para coleta de dados de todos os pacientes na unidade de hematologia e TCTH do HC-FMUSP que tinham resultado positivo para toxina A/B do C. difficile durante o período de janeiro 2007 a junho de 2011 e criado um banco de dados no programa Epiinfo. Os desfechos avaliados foram forma grave de doença e óbito até 14 dias da diarréia. Qui-quadrado para tendência foi usado para avaliar a incidência de diarréia por C. difficile durante o período do estudo. Resultados: Um total de 69 episódios foi identificado em 64 pacientes em 439 pacientes suspeitos. Na distribuição temporal o qui-quadrado para tendência evidenciou que o número de casos suspeitos de diarréia por C. difficile permaneceu estável (p=0,418), em contraste com o aumento do número de casos confirmados (p=0,0006). A incidência de diarréia por C. difficile por 1.000 pacientes variou de 0,65 a 5,45 durante o período do estudo. O qui-quadrado para tendência evidenciou aumento do número de casos confirmados de C. difficile nas unidades de TMO (p=0,00004) e Hematologia (p=0,006). Já, a incidência de diarréia por C. difficile por 1.000 neutropênicos dia variou de 0,78 a 5,45 durante o período do estudo. A maioria 68% dos pacientes era do gênero masculino, a média de idade foi 38 anos. A doença de base mais comum foi Leucemia mielóide aguda (44%), destes 46% estavam neutopênicos, 45% TCTH alogênicos, 88% dos pacientes usaram antibióticos prévios. A maioria dos pacientes 88% recebeu tratamento com metronidazol via oral, 37% tiveram resposta parcial nos primeiros sete dias de tratamento, 57% terminaram o tratamento e três pacientes tiveram recidiva, 24% evoluíram para óbito. A análise bivariada dos fatores de risco associados com a forma grave de diarréia por C. difficile, identificou o tipo de transplante alogênico como o único fator de risco significantivo, já a análise multivariada não identificou nenhum fator de risco independente. A análise bivariada de fatores de risco associados com óbito até 14 dias do diagnóstico de diarréia por C. difficile, identificou o tipo de transplante alogênico, forma grave de doença, internação em UTI e uso de linezolida como fatores de risco para óbito e Linfoma como protetor. Os fatores de risco independentes associados com óbito foram forma grave de doença, internação em UTi e uso de linezolida. Conclusão: A incidência de infecção por C. difficile durante o período do estudo aumentou, entretanto, a manifestação da forma grave da doença se manteve estável. Os fatores de risco independentes associados com óbito foram forma grave de doença, internação em UTI e uso de linezolida / Introduction: Diarrhea caused by Clostridium difficile is one of the main causes of infectious diarrhea associated with healthcare. Objective: To describe cases and the incidence of diarrhea by C.difficile in hematological and HSCT inpatients of the infirmary of Hematology and Bone Marrow Transplant of the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Methods: A form was used to collect data from all patients in the hematology and HSCT unit of the HCFMUSP who showed positive results for toxin A/B of the C. difficile during the period from January 2007 to June 2011, and to create a databank in the Epiinfo program. The outcomes evaluated were the severe form of the disease and death within 14 days of the [onset of] diarrhea. The Chi-squared test for tendency was used to evaluate the incidence of diarrhea by C. difficile during the study period. Results: A total of 69 episodes were identified in 64 patients in 439 suspect patients. In the temporal distribution, the chi-squared test for tendency evidenced that the number of cases of suspected diarrhea due to C. difficile remained stable (p=0.418), in contrast with the increase in number of confirmed cases (p=0.0006). The incidence of diarrhea by C. difficile per 1,000 patients varied from 0.65 to 5.45 during the study period. The chi-squared test for tendency demonstrated an increase in number of cases confirmed of C. difficile in the BMT TMO (p=0.00004) and Hematology (p=0.006) units. On the other hand, the incidence of diarrhea by C. difficile per 1,000 neutropenic individualsday varied from 0.78 to 5.45 during the study period. Most of the 68% of patients were of the male gender; the average age was 38 years. The most common underlying disease was acute myeloid leukemia (44%); of these, 46% were neutropenic, 45% HSCT allogeneic, and 88% of the patients had previously used antibiotics. Most of the patients (88%) received treatment with oral metronidazole, 37% had a response in the first seven days of treatment, 57% finished the treatment, three patients experienced relapse, and 24% died. The bivariate analysis of the risk factors associated with the severe form of diarrhea by C. difficile, identified the type of allogeneic transplant as the only significant risk factor, whereas the multivariate analysis did not identify any independent risk factor. Bivariate analysis of risk factors associated with death within 14 days of the diagnosis of diarrhea due to C. difficile, identified the type of allogeneic transplant, severe form of the disease, stay in the ICU, and use of linezolide as risk factors for death, and Lymphoma as a protector. Independent risk factors associated with death were the severe form of the disease, stay in the ICU, and use of linezolide. Conclusion: The incidence of infection by C. difficile during the study period increased; nevertheless, the manifestation of the severe form of the disease remained stable. The independent risk factors associated with death were the severe form of the disease, stay in the ICU, and use of linezolide

Clostridium difficile est une bactérie entéropathogène responsable de diarrhées nosocomiales post-antibiotiques et de colites pseudomembraneuses. Ces dernières années, l'incidence et la gravité des infections à C. difficile ont significativement augmenté en Amérique et en Europe. Cette évolution semble être liée à l'émergence puis à la dissémination très rapide d'un clone particulièrement virulent de PCR-ribotype 027. Les facteurs de virulence majeurs de C. difficile sont les toxines TcdA et TcdB qui sont responsables des lésions intestinales. Cependant, l’étape de colonisation de l’intestin par la bactérie est considérée comme un pré-requis à l’infection. Afin de mieux comprendre les mécanismes d’hypervirulence de la souche 027, nous nous sommes focalisés sur l’étude du processus de colonisation intestinal de cette souche en le comparant à celui de la souche non épidémique 630∆erm. Dans un premier temps, nous avons étudié le rôle de la protéine de liaison à la fibronectine FbpA. La caractérisation in vitro et in vivo d’un mutant d’inactivation de fbpA, nous a permis de montrer l’implication de cette protéine dans le processus de colonisation de la souche non épidémique 630∆erm. La difficulté à obtenir un mutant dans la souche épidémique 027 R20291 ne nous a pas permis de comparer les propriétés adhésives de FbpA entre les deux souches. Dans un deuxième temps, nous avons étudié les caractéristiques des protéines flagellaires FliC, FliD, FlgE et MotB. Nous avons montré que les flagelles agissent en tant qu’adhésines chez la souche 027 et que ce rôle est moins important chez la souche 630∆erm. Nous avons également montré que les flagelles sont impliqués dans des processus cellulaires autres que l’adhésion et la colonisation. Selon une étude transcriptomique d’un mutant ∆FliC de la souche 027 R20291, il s’est avéré que la flagelline est aussi impliquée dans la production de toxines, la sporulation et dans l’adaptation de la bactérie aux conditions de stress. Une étude complémentaire serait nécessaire afin de mieux comprendre le système de régulation qui régi ces différents processus cellulaires.Finalement, nous avons effectué une analyse transcriptomique de la cinétique de colonisation in vivo de la souche 027. L’étude a révélé l’expression précoce des gènes de toxines et de sporulation au cours du processus d’infection. Elle nous a également permis d’identifier des gènes spécifiques à la souche 027 qui sont exprimés lors du processus infectieux. Ces gènes pourraient éventuellement être impliqués dans la virulence de C. difficile 027 et pourraient constituer de nouvelles pistes d’étude. / Clostridium difficile is an enteropathogenic bacterium that causes post-antibiotic nosocomial diarrhea and pseudomembranous colitis. During the last decade, the incidence and the severity of C. difficile infections have significantly increased in America and Europe. This evolution seems to be related to the emergence and to the rapid dissemination of a particularly virulent clone of PCR-ribotype 027. The main virulence factors of C. difficile are the TcdA and TcdB cytotoxins which are responsible for intestinal lesions. However, the intestinal colonization by the bacterium is considered as an indispensible step for infection.To better understand the hypervirulence mechanisms of strain 027, we focused on the study of intestinal colonization process of this strain compared to the colonization process of the non-epidemic strain 630Δerm. First, we studied the role of the fibronectin binding protein FbpA. In vitro and in vivo characterization of a mutant FbpA showed the involvement of this protein in the colonization process of the non-epidemic strain 630Δerm. The difficulty of obtaining a mutant in the epidemic strain R20291 027 does not allow us to compare the adhesive properties of FbpA between the two strains.In a second step, we studied the characteristics of flagellar proteins FliC, FliD, FlgE and MotB. We showed that the flagella have a role in the adhesion and colonization of strain 027 and that this role is less important in strain 630Δerm. We also showed that flagella are involved in other cellular processes than adhesion and colonization. A transcriptomic study of a FliC mutant in 027 R20291 shows that flagellin is also involved in toxin production, sporulation and in the adaptation of bacteria to stress conditions. Further study should be performed to better understand the regulation system that governs these different cellular processes. Finally, we performed a transcriptomic analysis of the kinetic of in vivo colonization of the 027 R20291 strain. The study revealed a very early expression of toxin and sporulation genes during the first stages of the infection process. This analysis also allowed us to identify some genes, specific to 027 strains, which appeared regulated during the infection process. These genes could be involved in the virulence of C. difficile 027 strains and could provide new issues of study to better understand C. difficile virulence.

Introdução: A diarréia por Clostridium difficile é uma das principais causas de diarréia infecciosa associada à assistência à saúde. Objetivo: Descrever os casos e a incidência de diarréia por C. difficile em pacientes hematológicos e TCTH internados na enfermaria da Hematologia e do Transplante de Medula óssea do Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Métodos: Foi utilizada uma ficha para coleta de dados de todos os pacientes na unidade de hematologia e TCTH do HC-FMUSP que tinham resultado positivo para toxina A/B do C. difficile durante o período de janeiro 2007 a junho de 2011 e criado um banco de dados no programa Epiinfo. Os desfechos avaliados foram forma grave de doença e óbito até 14 dias da diarréia. Qui-quadrado para tendência foi usado para avaliar a incidência de diarréia por C. difficile durante o período do estudo. Resultados: Um total de 69 episódios foi identificado em 64 pacientes em 439 pacientes suspeitos. Na distribuição temporal o qui-quadrado para tendência evidenciou que o número de casos suspeitos de diarréia por C. difficile permaneceu estável (p=0,418), em contraste com o aumento do número de casos confirmados (p=0,0006). A incidência de diarréia por C. difficile por 1.000 pacientes variou de 0,65 a 5,45 durante o período do estudo. O qui-quadrado para tendência evidenciou aumento do número de casos confirmados de C. difficile nas unidades de TMO (p=0,00004) e Hematologia (p=0,006). Já, a incidência de diarréia por C. difficile por 1.000 neutropênicos dia variou de 0,78 a 5,45 durante o período do estudo. A maioria 68% dos pacientes era do gênero masculino, a média de idade foi 38 anos. A doença de base mais comum foi Leucemia mielóide aguda (44%), destes 46% estavam neutopênicos, 45% TCTH alogênicos, 88% dos pacientes usaram antibióticos prévios. A maioria dos pacientes 88% recebeu tratamento com metronidazol via oral, 37% tiveram resposta parcial nos primeiros sete dias de tratamento, 57% terminaram o tratamento e três pacientes tiveram recidiva, 24% evoluíram para óbito. A análise bivariada dos fatores de risco associados com a forma grave de diarréia por C. difficile, identificou o tipo de transplante alogênico como o único fator de risco significantivo, já a análise multivariada não identificou nenhum fator de risco independente. A análise bivariada de fatores de risco associados com óbito até 14 dias do diagnóstico de diarréia por C. difficile, identificou o tipo de transplante alogênico, forma grave de doença, internação em UTI e uso de linezolida como fatores de risco para óbito e Linfoma como protetor. Os fatores de risco independentes associados com óbito foram forma grave de doença, internação em UTi e uso de linezolida. Conclusão: A incidência de infecção por C. difficile durante o período do estudo aumentou, entretanto, a manifestação da forma grave da doença se manteve estável. Os fatores de risco independentes associados com óbito foram forma grave de doença, internação em UTI e uso de linezolida / Introduction: Diarrhea caused by Clostridium difficile is one of the main causes of infectious diarrhea associated with healthcare. Objective: To describe cases and the incidence of diarrhea by C.difficile in hematological and HSCT inpatients of the infirmary of Hematology and Bone Marrow Transplant of the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Methods: A form was used to collect data from all patients in the hematology and HSCT unit of the HCFMUSP who showed positive results for toxin A/B of the C. difficile during the period from January 2007 to June 2011, and to create a databank in the Epiinfo program. The outcomes evaluated were the severe form of the disease and death within 14 days of the [onset of] diarrhea. The Chi-squared test for tendency was used to evaluate the incidence of diarrhea by C. difficile during the study period. Results: A total of 69 episodes were identified in 64 patients in 439 suspect patients. In the temporal distribution, the chi-squared test for tendency evidenced that the number of cases of suspected diarrhea due to C. difficile remained stable (p=0.418), in contrast with the increase in number of confirmed cases (p=0.0006). The incidence of diarrhea by C. difficile per 1,000 patients varied from 0.65 to 5.45 during the study period. The chi-squared test for tendency demonstrated an increase in number of cases confirmed of C. difficile in the BMT TMO (p=0.00004) and Hematology (p=0.006) units. On the other hand, the incidence of diarrhea by C. difficile per 1,000 neutropenic individualsday varied from 0.78 to 5.45 during the study period. Most of the 68% of patients were of the male gender; the average age was 38 years. The most common underlying disease was acute myeloid leukemia (44%); of these, 46% were neutropenic, 45% HSCT allogeneic, and 88% of the patients had previously used antibiotics. Most of the patients (88%) received treatment with oral metronidazole, 37% had a response in the first seven days of treatment, 57% finished the treatment, three patients experienced relapse, and 24% died. The bivariate analysis of the risk factors associated with the severe form of diarrhea by C. difficile, identified the type of allogeneic transplant as the only significant risk factor, whereas the multivariate analysis did not identify any independent risk factor. Bivariate analysis of risk factors associated with death within 14 days of the diagnosis of diarrhea due to C. difficile, identified the type of allogeneic transplant, severe form of the disease, stay in the ICU, and use of linezolide as risk factors for death, and Lymphoma as a protector. Independent risk factors associated with death were the severe form of the disease, stay in the ICU, and use of linezolide. Conclusion: The incidence of infection by C. difficile during the study period increased; nevertheless, the manifestation of the severe form of the disease remained stable. The independent risk factors associated with death were the severe form of the disease, stay in the ICU, and use of linezolide

Community-acquired Clostridium difficile infections have recently been increasing in incidence and severity. Several studies have isolated C. difficile spores from livestock and retail meats, suggesting that food may play a role in transmission. No research has been done, however, on what food conditions might allow for the survival and/or growth of the bacterium. We therefore modelled the minimum thresholds for C. difficile growth under low pH, water activity (aw), and temperature. We also sampled retail ground meats, cheese, and milk for the presence of C. difficile spores and subtyped food isolates for comparison with clinical strains. We found that C. difficile growth could be prevented by refrigeration temperatures. C. difficile spores were also detected for the first time in Canada in ground lamb, ground turkey, ground chicken, cheese and milk. The majority of these food isolates were genetically similar to epidemic strain NAP7/078, suggesting that food may not be a direct vector for C. difficile transmission, but could still be clinically relevant.

Source: Masters Abstracts International, Volume: 47-06, page: 3546. Advisers: Zhi-Dong Jiang; Linda B. Piller. Includes bibliographical references.

Introduction: Clostridium difficile infection (CDI) is a common hospital-acquired infection and a financial burden on the healthcare system. There is a need to reduce its impact on patients and the entire health system. More accurate estimates of the financial impact of CDI will assist hospitals in creating better CDI reduction strategies with limited resources. Previous research has not sufficiently accounted for the skewed nature of hospital cost data, baseline patient mortality risk, and the time-varying nature of CDI. Objective: We conducted a retrospective cohort study to estimate the cost impact of hospital-acquired CDI from the hospital perspective, using a number of analytical approaches. Method: We used clinical and administrative data for inpatients treated at The Ottawa Hospital to construct an analytical data set. Our primary outcome was direct costs and our primary exposure was hospital-acquired CDI. We performed the following analyses: Ordinary least square regression and generalized linear regression as time-fixed methods, and Kaplan-Meier survival curve and Cox regression models as time-varying methods. Results: A total of 49,888 admissions were included in this study (mean (SD) age of 64.6 ± 17.8 years, median (IQR) baseline mortality risk of 0.04 (0.01-0.14)). 360 (0.73%) patients developed CDI. Estimates of incremental cost due to CDI were substantially higher when using time-fixed methods than time-varying methods. Using methods that appropriately account for the time-varying nature of the exposure, the estimated incremental cost due to CDI was $8,997 per patient. In contrast, estimates from time-fixed methods ranged from $49,150 to $55,962: about a six fold difference. Conclusion: Estimates of hospital costs are strongly influenced by the time-varying nature of CDI as well as baseline mortality risk. If studies do not account for these factors, it is likely that the impact of hospital-acquired CDI will be overestimated.

Community-acquired Clostridium difficile infections have recently been increasing in incidence and severity. Several studies have isolated C. difficile spores from livestock and retail meats, suggesting that food may play a role in transmission. No research has been done, however, on what food conditions might allow for the survival and/or growth of the bacterium. We therefore modelled the minimum thresholds for C. difficile growth under low pH, water activity (aw), and temperature. We also sampled retail ground meats, cheese, and milk for the presence of C. difficile spores and subtyped food isolates for comparison with clinical strains. We found that C. difficile growth could be prevented by refrigeration temperatures. C. difficile spores were also detected for the first time in Canada in ground lamb, ground turkey, ground chicken, cheese and milk. The majority of these food isolates were genetically similar to epidemic strain NAP7/078, suggesting that food may not be a direct vector for C. difficile transmission, but could still be clinically relevant.

Diss. (sammanfattning) Stockholm : Karol inst., 2004. / Härtill 5 uppsatser.

Source: Masters Abstracts International, Volume: 46-04, page: 2097. Adviser: Herbert L. DuPont. Includes bibliographical references.

A diarréia é o principal evento clínico observado no período neonatal em leitões (como conseqüência das doenças entéricas). Além de contribuir para piora no ganho de peso diário e conversão alimentar do animal causa aumento na mortalidade e gastos com medicamentos. O presente trabalho teve como objetivo determinar a freqüência dos principais agentes virais (rotavírus), bacterianos (E. coli, Clostridium perfringens tipo A e C e Clostridium difficile) e parasitários (coccídeos e Cryptosporidium spp.) envolvidos na diarréia neonatal em leitegadas caso (com diarréia) e controle (sem diarréia). Foram examinadas 276 amostras de fezes provenientes de 147 leitegadas com diarréia e 129 leitegadas sem diarréia, com idade variando entre 1 e 7 dias de vida em 28 unidades produtoras de leitões localizados no Estado do Rio Grande do Sul. Entre as amostras coletadas, 29,34% (81/276) foram positivas para pelo menos um agente pesquisado. Os coccídeos (20/276) e o C. perfringens tipo A (19/276) foram os agentes mais freqüentes. Nenhum dos enteropatógenos pesquisados obteve diferença significativa (p>0,05) entre as leitegadas caso e controle. Apenas o rotavírus (p=0,20) e o C. perfringens tipo A (p=0,16) apresentaram tendência de serem mais freqüentes em leitegadas com diarréia. Uma forte associação foi observada entre a ocorrência das diarréias e leitegadas mais novas (p<0,014). Foi observada pela primeira vez no Brasil a infecção pelo C. difficile, em 13,6% (17/132) das amostras, todavia a presença das toxinas nas fezes não teve relação com a diarréia. Os resultados obtidos indicam a necessidade de cuidados especiais quando da coleta de amostras para diagnósticos de monitoria de diarréias no período neonatal, pois é alta a chance de se obterem resultados falso positivos naqueles casos em que as doenças estiverem ocorrendo numa forma endêmica. / Diarrhea is the main clinical event occurring in pigs in the neonatal period,(as consequence of enteric disease). Besides contributing to losses in daily weight gain and feed conversion, diarrhea causes increased mortality and medication costs. The present work aimed to determine the frequency of the main viral agents (rotavirus), bacterial (E. coli, Clostridium perfringens type A and C and Clostridium difficile) and parasitic (coccidian and Cryptosporidium spp.) involved in neonatal diarrhea in case groups (with diarrhea) and controls (without diarrhea). We examined 276 fecal samples originating from 147 litters with diarrhea and 129 litters without diarrhea, with ages varying between 1 and 7 days, in 28 pig units of the state of Rio Grande do Sul, Brazil. Among the examined samples, 29.34% (81/276) were positive for at least one agent. Coccidia (20/276) and C. perfringens type A (19/276) were the most frequently isolated agents. None of the enteropathogens studied showed significant difference (p>0.05) between case and control litters. Only rotavirus (p=0.20) and C. perfringens A (p=0.16) had a tendency to present higher frequency in piglets with diarrhea. A strong association was observed between occurrence of diarrhea and litters with smaller age (p<0,014). Infection with C. difficile was diagnosed for the first time in Brazil, in 13.6% (17/132) samples; however the presence of the toxin in feces was not related to diarrhea. The present results suggest the need for special attention when sampling for the diagnosis or monitoring diarrhea in the neonatal period, as chances for obtaining false-positive results are high, especially when diseases are occurring endemically.